1. Field of the Invention
The present invention relates to a medical robot system using a medical manipulator having a distal-end joint operable by flexible members that are actuated by actuators.
2. Description of the Related Art
According to a laparoscopic surgical operation process, small holes are opened in the abdominal region, for example, of a patient, and an endoscope and manipulators or forceps are inserted into such holes. The surgeon performs a surgical operation on the patient with the manipulators or forceps, while watching an image captured by the endoscope and displayed on a display monitor. Since the laparoscopic surgical operation process does not require a laparotomy to be performed, the operation is less burdensome on the patient and greatly reduces the number of days required for the patient to spend in the hospital before recovering from the operation and being released from the hospital. Therefore, the range of surgical operations in which the endoscopic surgical operation process may be applied is expected to increase.
As disclosed in Japanese Laid-open Patent Publication No. 2002-102248 and Japanese Laid-open Patent Publication No. 2003-061969, a manipulator system comprises a manipulator and a controller for controlling the manipulator. The manipulator comprises an operating unit, which is manually operated, and a working unit replaceably mounted on the operating unit.
The working unit comprises a long joint shaft and a distal-end working unit (referred to as an “end effector”) mounted on the distal end of the joint shaft. The operating unit has motors for actuating the working unit through wires. The wires have proximal end portions wound around respective pulleys. The controller energizes the motors of the operating unit to cause the pulleys to move the wires circulatively.
There has also been proposed a medical robot system for actuating medical manipulators with robot arms (see, for example, U.S. Pat. No. 6,331,181). The medical robot system can be remotely controlled by a master arm, and can be moved in various ways under a programmed control.
The medical robot system has the robot arms, which can selectively be used depending on the surgical technique required. One of the robot arms incorporates an endoscope therein for capturing an image representing the inside of a body cavity, which is capable of being visually confirmed on a display monitor.
According to the laparoscopic surgical operation process, it is desirable to provide a wider operative field in the body cavity being operated on of the patient because the wider operative field allows the manipulators to operate with greater freedom in the body cavity.
The body cavity may contain various organs in addition to the organ as the affected region, which make it difficult to provide a wide operative field in the body cavity. The manipulator on one of the robot arms of medical robot systems may be used as a retractor for retracting an organ or organs other than the affected region to a position out of interference with the surgical operation.
However, when the organ or organs are retracted by the retractor, the retractor itself may be positioned across the body cavity, and present itself as an obstacle in the operative field.